Surprising Fish Cousins: Tuna & Seahorses

A new spiny-rayed fish family tree shows tuna and seahorses are closely related through a common ancestorSpiny-rayed fish rule the underwater world.In the past 100 million years, fish with spiky dorsal and anal fins — an effective anti-predator device — have occupied every nook and cranny of the planet, said Peter Wainwright, an evolutionary biologist at the University of California, Davis. The group includes more than 90 percent of coral reef fish species and almost everything humans commercially fish, including bass, pollock and tilapia.Now, Wainwright and a team of researchers have pieced together a new family tree for this gigantic brood, with more than 18,000 species living today. Using both genetic tools and fossils, the "phylogeny" reveals unexpected links between some spiny-rayed fish, such as tuna and seahorses. The findings were published July 15 in the journal Proceedings of the National Academy of Sciences.